uploadify button not working in firefox, works fine in chrome and IE

Question

I have a uploadify button:

    <input id="fileUpload" name="stream" type="file" />

Then I have some javascript to handle it:

        $('#fileUpload').uploadify({
            multi: true,
            removeTimeout: 0,
            method: 'post',
            successTimeout: 3600,
            width: 200,
            height: 55,
            buttonClass: 'btn btn-primary btn-large pull-left',
            buttonText: 'Select file',
            swf: baseUrl + 'Scripts/uploadify.swf',
            uploader: baseUrl + 'AssetQuery/FindAssets/FindAssetsByFile',
            onUploadStart: function () {
                blockScreen(true);
            }
          .......

The problem is the button only works in chrome and iE. the file dialog does not even come up when running in firefox. I have the latest flash installed and using the latest uploadify. Clicking the button doesn't even trigger any console logs. any ideas?